1. Field of the Invention
The present invention relates to a transmission terminal to transmit and receive image data and voice data to and from a device connected to the transmission terminal via a network.
2. Description of the Related Art
In recent years, a videoconference system to conduct videoconferences between remote places via communication networks, such as the Internet, is becoming increasingly popular.
Videoconferencing is communication with others using video and audio software and hardware to see and hear each other. To conduct such a videoconference, the videoconference system uses transmission terminals (which may also be referred to as “terminals”) which are arranged in a conference room of one of the remote places where persons concerned, such as attendants of the videoconference, are present. Each of the transmission terminals collects voices of the persons concerned, such as discussions in the videoconference, and captures images of the conference room and the persons concerned, converts the voices and the images into digital data, and transmits the digital data to the other party's transmission terminal via a network, such as the Internet. The digital data is received at a transmission terminal of the other party's conference room, and the received data is reproduced and output by a speaker and a display device of the transmission terminal as image data and audio data. In this manner, the videoconference is conducted between the remote places in the conditions closely resembling reality.
In the videoconference system of this kind, all transmission terminals and a video delivery server which participate in a videoconference are connected together. The video delivery server controls distribution of image data and audio data to the respective transmission terminals, and the videoconference may be implemented as a multipoint distribution service.
One of the major problems arising on the transmission terminals in the videoconference system is that image data and voice data are not transmitted correctly. Causes of the problem may include a fault of the transmission terminal hardware, a fault of the transmission lines between the transmission terminals and the video delivery server through the Internet, or a lack of network bandwidth capacity needed for conducting the videoconference.
To perform troubleshooting of each of the transmission terminals, the following methods may be used. A user may check the content of a fault of the transmission terminal concerned by executing a self-diagnosis function of the transmission terminal. A service person may visit the site of a user and check a defective transmission terminal body. If the service person cannot discover a fault of the transmission device on the site, the transmission device may be carried to a service center of a manufacturer and troubleshooting of the defective transmission device may be performed by analysis using a special maintenance tool.
However, from the reasons of security and quality assurance, use of some of maintenance functions for finding out faults of terminal devices is restricted only to authorized service persons. For example, see Japanese Laid-Open Patent Publication No. 2004-303215. Japanese Laid-Open Patent Publication No. 2004-303215 discloses an electronic device where a level of maintenance which is permitted to be conducted is set beforehand. The electronic device includes an authentication unit which authenticates a person who intends to conduct maintenance of the electronic device, and an alteration unit which temporarily allows maintenance in response to an altering instruction if the person who intends to conduct maintenance of the electronic device is authenticated by the authentication unit.
In this connection, there are two authentication methods that are used to authenticate a service person in order to permit the service person to conduct maintenance of a device: online authentication and offline authentication. Online authentication is an authentication method by which service persons are authenticated by a server connected to the device via a network. Offline authentication is an authentication method by which service persons are locally authenticated without using communication via a network.
The security levels at which the two authentication methods are used are different from each other, and it is preferred that the maintenance range permitted for service persons when the offline authentication is used is more limited than that when the online authentication is used. However, in the maintenance of the conventional electronic devices according to the related art including Japanese Laid-Open Patent Publication No. 2004-303215, there is no definition or indication of the maintenance range when the offline authentication is used and of the maintenance range when the online authentication is not available.